Eecupeeator



Patented Dee. 12,1922.

3 SHEETS-SHEET 2.

R. scHLEMn/l. REcUPERAToR.

l APPLICATION FILED OCT- 14. |920.

RL SCHLEMM.

RECUPEAHATOR.Y APPLlCATION `FILED OCT. 14, |920.

,I i n. m 7 1 049m f RMP...) 1 n 7. L A L nJ of f.

m 1 H a y wv Patented Dec.. l2, 1922, l

tisane Unirev sir Nrsf rarifiia'rv OFFICE.

ROBERT SCELEMM, F CHICAGO, ILLINOIS.v

" y nncuinnnron.

i Application ledctoner 14, 1920. Serial No. 416,938.k

To @ZZ whom t may'concera: i

Be it known thatl, Renner SoiiLiiMM, citizen of the United States, and aresident of Chicago, in the county of Coolr'and State of Illinois, haveinvented a new and useful Recuperator, of which the following is aspecification.

This invention relates to recuperators o'csigned and adapted for heatingair supplied to furnaces byineans of the hot waste gases dischargedytherefrom. e

A principal object of my invention is to provide a recuperatorinwhichair entering the furnace and the waste `gases escaping therefromwill traverse` adjacent fluesor passageways separated by walls comm onto both thereof, said walls being made of material, as sheet steel,which is a good conductor of heat and which may be corrugated, ifvdesired, to increase the arca of radiating surfaces thereof, and therelation being such that the currents of air and of Waste gases willtraverse their respective lines in opposite direction, the airpreferably entering the air flue or flues substantially at they point ofdischarge of the waste gases and escaping therefrom at the point wherethe waste y,( ffises enter the waste gas flue or flues, whereby the iair will enter and pass through Zones of pro-` gressively increasingtemperatures, and a substantially uniform thermal head or teniy peraturedifference between the air and waste Y,

gases will be maintained, which, as is'wcll known, will conduce to themost efficient operation ofthe recuperator.L v

With the described construction, itis ol vious that by inalriifg saidflues of proper length, thev temperature ofthe waste gases leaving therecuperator may bereduced to that of theair-entering the' recuperatorand the airdischarged frein said"recuperare-i`` will be heatedtoapproximately the teiinpera` ture of the waste gasesentering said recu-kperator: in` other words, that 4`substantial ly all available thermalunits will be extracted from said waste gases and absorbed by the airsupplied to the furnace, resulting kin much more vigorous and perfectcombustion of the fuel, with corresponding saving in the quantity offuel used.

F or purposes of convenient reference, my

economy am? after described and claimed.

improved recuperator may appropriately be designed a counter-flowrecuperator.

In practice, I effectr the foregoing object of the invention, bytheuseof a plurality of spaced stacks arranged one within another,preferably in concentric relation, forming separate flues comprisingairsupply fines and a waste gas flue arranged intermediate said airsupply fines. That is, I provide a plurality of air and waste gas stacksarranged in alternate relation, both the ei:-

`treme inner and outer stacks, forming air supply flues, said gas staclror staclrs conimunicating with the breeching'of lthe boiler anddischarging into the air, and the air supply stacks or fines alldischarging into 'a common chamber, a Aconsta-nt circulation` of airbeing maintained downwardly in the air supply flues into said chamberand from said chamberto the combustion chamber of the furnacey by a fanor injector adapted for 'exhausting air from said chamber` anddischarging it into the combustion space of the y furnace. I

A further object of the invention is to provide means for preventing thewaste, burntout gases from being drawn into the air sup-- ply iiues andreturned to the furnace, which Vwould operate to correspondingly reducethe maximum efficiency of thefurnace in operation. l y y This object Ieffect, by means of a. hood secured to the upper end of the waste gasstack, which opens throughthe top'tliereof, said hood being spaced rfromthe outer air stack and the lower end thereof being open to permit airto enter the same,.theuppei" endjof the outer air flue communicatingdirectly with said hood and thev inner air flue or fines communicatingtherewith by 4means of a passageway or passageways extending across thegas flue, the sides'of saidpassageways being closed to prevent wastegases from entering the saine. Said hood is made of any' lengthknecessary to prevent `waste gases discharged from the recuperator frombeing drawn into the open lower end thereof.

ll/iy` improved recuperator also comprises the various other features,combinations of features and details of construction hereinln theaccompanying drawings in which my invention is fully illustrated, thefigures of the drawings being to a. large extent diagrannnatic,

Figure l, is a side elevation of a recuperator or' my invention shown asapplied in use to a steam boiler.

Figure 2, is an end elevation thereof taken from the right hand side ofFigure l.

Figure 3, is an enlarged elevation thereof, partly in section on theline 3-3 oi' Figures 5 and 6.

Figure d, is a top plan view thereof.

Figure 5, is an elevation of said recupera tor at ninety degrees :fromthat shovmi in Figure 3, said view being partly in section on tho line5-5 of Figure Figure is a transverse sectional View on the line 6-6 ofFigure 6.

Figure 7, is an elevation oi' my improved recuperator shown as appliedto use to a battery of forges.

Figure 8, is an elevation thereof from the right hand side of Figure 7.

Figure 9, is a detached enlarged side view, partly in sections, oi` therecuperator shown in Figure 8, illust-rating the manner of supplying airthereto; and

Figure l0, is a top plan view thereof.

Referring now particularly to Figures l to G ot the drawings, Adesignates, as a whole, a recuperator of my invention shown as appliedin use to a steam boiler, designated. as a whole B, to the combustionchainber of which air under forced draft is adapt ed to be supplied fromthe recuperator i by means oi: a blower B1, which is connected into apipe comprising a section Z), which connects said blower with therecuperator, and a section b1, which connects said blower withthecombustion chamber oi the boiler.

is shown, the boiler B is of the `familiar type known to the trade asBabcock and Wilcox boilers. However, the use and application oit myimproved recuperator is in no waff dependent upon the type of boiler.but admits oil a. wide range of application and use in connection withpractically all 'forros oif boilers ol" which l have any presentknowledge, and l do not therefore desire to limit myseltx to thespecific application shown or Ato use with any particular form or 'typeof boiler@ Likewise the tan B1, which is shown diagrainiuatically only,may be of any usual or desired construction, it being possible topurchase many ditlerent forms oiI fans suitable iior the purpose in theopen market.

in acco`dance with my invention, the recuperator lli., comprises aplurality7 oi' stacks l, 2 and 8, arranged one within the other,preferably in concentric relation, and which deiine fines ci? 4l., 5 andG.

Adjacent to its lower end, the intermediate stack il, communicates withthe breechinsegne ing or waste gas space of the boiler B, the wastegases from which are discharged through the intermediate flue 5 deiinedby the inner stack l and the intermediate stack 2, passing upwardlytherethrough, while the air for supporting combustion in the boiler'furnace passes downwardly through the iiues or passageways e and 6,respectively defined or 'formed by the inner stack l and by the stacks 2and 3, the outer stack 3 being connected directly to the intake ot theian B1 and the inner stack l passing through the wall of theintermediate stack 2 and opening directly into the lower end ot theouter stack 3, `With this connection, itis obvious that. in opere ion,the fan i 1 will create and maintain currents oit air downwardly throughthe lues 4l and 6.

For purposes oi convenient reference. the intermediate Hue 5 willhereinafter desig nate the waste gas iiue and vthe 'fines el and G theinner and outer air supply tlues.

To provide access to the waste gas flue 5, for cleaning' the same andtor otherpurposes, the lower end ot the intermediate stack 2 comprisesan extension 7, which' eittends downwardly at an angle to said stackproper and which opens through the outer stack 3 adjacent to its lowerend, the open lower end thereof being closed by a remov-.

able cover plate 8.

To prevent the waste, burned-out gases discharged rom the waste gasAflue 5 from en- "ng the air supply i'iues and thus contamina ing theair supply, a hood 9 supported at the upper ends ot the stack 2. saidstack 2 opening through the top ot said hood and said hood extendingdownwardly outside ot the outer stack 3 so as to enclose the open upperend thereof, said hood being sutiiciently larger than said stack 3 totorni a passageway l0 through which air may enter the open upper end oi"said stack. Also, the enclosed upper enc ot said hood is connected withthe upper end ot the inner air vflue by n sans of elbows or branch pipesll', which entend across lthe waste gus liuc and open through the Vallsoi' the inner stack l and intermediate stack 2, preierably above the topotthe outer stack 3.

lWith the descrioed construction, all air supplied to the boiler furnacewill enter the lower end of the hood 9, which may be made of any lengthnecessary to insure that waste gases discharged from the waste ilue 5will not be drawn into said hood.

To prevent radiation of heat from the outer stack 3. said stack ispreferably corered with suitable insulating material, as magnesia orasbestos, indicated at l2, said insulation preferalilyterminating belowthe lower end of the hood 9.

For use in connection with steam boilers and in other application wheretei peratures are comparatively low, the stacks l,

temperature applications, the lower sections of the recuperator--Wherethe high temperatures obtain-Will be made of specialy heat resistingsheet metal or Where teinpuerlatures run very high, of refractorymateria. f

Also, to increase the radiating surfaces oi theinner stacks 1 and 2,they may be corrugated, as shown at v13. f y

With the described construction, it is obvious that, by making thestacksl 1, 2 and 3 of proper length, the Waste gases will be dischargedfrom the recuperator practically at atmospheric temperature, While theair supplied to the furnace will be heated substantially to thetemperature of the Waste lgases Where they Aare discharged from thecombustion chamber or Waste gas space of the boiler, and that., in thismanner, practically all heat units, which otherwise would pass to Wastewith the Waste gases from thewboiler, would be reclaimed and returned tothe furnaceof the boiler, thus not only conserving heat andcorrespondingly reducing the quantity of fuel required, but, through thepreheating of the air, producing a much more vigorous combustion and acorrespondingly intense heat-all resulting in ay greatly increasedeliiciency in the operationof the boiler or other heating apparatus,with. a corresponding reduction and economy in fuel consumption. t I

As a modification of my rimproved recuperator, l contemplate aconstruction in whi ch access of Waste gases to the fair supply tlueswill be prevented Without the use of thehood shown in Figs. 1 to 6.

This modification of my improved re-A cuperator is illustrated inFigures 7 to 10 of the drawings in Which l have shown re-` cuperators ofiny invention as applied inuse to a battery of forge furnaces. u

Referring new to said Figs. 7 to 11,1)

represents one of a battery of any number of forge or other furnace. "Asshown, said furnace is an oil burning furnace, the fuel oil beingdelivered to the combustion space thereof through pipesflll, andk airunder pressure for effectingv combustion of said fuel oil being suppliedthereto through pipesiues 4:1, 51 and 61, the innery and outer fines 41and 61 being the air supply flues and the intermediate flue 51vbeing theWaste gas Hue, and the air supplied to the furnace being heated bylradiation from the stacks 11` and 21 which dei'ine the Waste gas flueG1 and are heated by the hot Waste gases discharged therethrough, all asfully explained in connection with the form of recuperator shown inFigures 1 to 6.

As shown in said Figures 7 to 10, the innerand outer air supply iiues/11 to 61 are connected, both at their upperand lower ends, by branchpipes or elbows 1G which extend across the intermediate waste gas flue51, and air under pressure is admitted theretodirectly from an air trunk17"--l Which communicates With a source of supply of air under pressure,as shown With a` end Vof the outer air supply liue 61 of the Which theWaste gases from the rfurnace pass into'said Waste gas flue. t

The elbows 16 close both the kupperand lower ends of the stack 11 andthe upper end of the outer air flue 61 is closed by a plate 21 which is,providedk with a hole through ivhich the Waste gas stack 21 eX- tends,said Waste gas stack being preferably made of such length that it Willextend through the roof of the buildingindicated I claim: 1;. 1n arecuperator, the combination of a plurality of stacks arranged onewithin another forming separate fines comprising air supply flues and aWaste gas flue arranged intermediate said air supply lines, theinnerstacks between Waste gas and vair supply fines being iliade ofiiiateiial which a conductor of heat, the lower ends of said air supplylines being adapted to be` connectedk With the combustion chamber of afurnace and being provided at their upper ends With air supplyconnections, the lower end of the Waste gas flue being adapted forconnection with the Waste gas space of a furnace and means for creatinga circulationof airin said supply fiues in a direction` opposite to the.circulation ofivaste gases in said Waste gas iiue, substantially asdescribed.

2. ln a reeuperator, the combination of a plurality of stacks arrangedone Within yanother forming separate fines comprising air supply fluesand a Waste gas flue arranged intermediatesaid air supply itlues, `theinner stacks between Waste gas and air supllO ply tlues being made ofmaterial which is a conductor of heat, the lower ends otsaid air supplyilues being adaptedto be connected with the combustion chamber of' a'furnace and being provided at their upper ends with air supplyconnections, thelower end of the waste gas flue being adapted forconnection with the waste gas space of a furnace, means for creating acirculation of air in said air supply tlues in a direction opposite tothe circulation ot waste gases in said waste gas flue, and means toprevent waste gases discharged from said waste gas tlue trom enteringthe air supply iiues, substantially as described.

3. ln a recuperator, the combination of a plurality of stacks arrangedone within another forming separate tiues comprising air supply tluesand a waste gas tlue arranged intermediate said air supply iiues, theinner staclrs between waste gas and air supply tlues being made ofmaterial which is a conductor ot heat, the lower ends of said air supplylines being adapted to be connected with the' combustion chamber ot afurnace and being provided at their upper ends with air sup plyconnections, the lower end of the waste gans flue being adapted iorconnection. with the waste gas space ot a furnace and means tor creatinga circulation ot air in said air supply tlues in a direction opposite tothe circulation etwaste gases in said waste gas i'lue, the operativelengths oit said air supply and waste gas fines being substantiallyequal and coincident, substantially as described.

4t. ln a recuperator, the combination or a plurality of stacks arrangedone within anotherl forming separate iiues comprising air supply tluesand a waste gas iiue arranged intermediate said air supply tlues theinner stacks between waste gas and air supply iiues being` made ofmaterial which is a conductor ot heat, the lower ends oit said. airsupply tlues being adapted to be connected with the combustion chamberot a turnaco and being provided at their upper ciuls with air supplyconnections, the lower' end ol' the waste gas line being adapted torconnection with the waste gas space ot a :tui-nace, and means 'torcreating a circulation oi" air in said air supply ilues in a directionopposite to the circulation of waste gases in said waste gas flue7 theoperative lengths of said air supply and gas lues being substantiallyequal and coincident, and said stacks being so proportioned that thewaste gases will be discharged from said recuperator approximately atatmospheric temperature, substantially as described.

5. In a recuperator, the combination of a plurality of stacks arrangedone within another torming separate tlues comprising air supply linesand a waste gas flue arranged intermediate said air supply lues, theinner stacks between waste gas and air supmessage ply tiues being madeot a material which is a conductor ot" heat., thev lower ends ot saidair supply lues being adapted to be con nected with the combustionchamber of a furnace and their upper ends being provided with airadmission openings, the lower end of said waste gas line being adaptedto be connected with the waste gas space ot a furnace, the waste gasespassing upwardly through said wasteV gas flue, means for creating acirculation of air downwardly through said air supply dues, and a hoodwhich encloses the upper end of the'staclr defining the outer air supplyflue, and is supported in spaced relation thereto, said hood being ofsuch length that it will prevent waste gases discharged irom the wastegas flue from entering its open lower end. and a branch pipe` or pipes`which connect the interior of said hood with the inner air supply flue.substantially as described.

6. ln a recuperator, the 'combination ot a plurality ot stacks arrangedone within another forming separate tiues comprising air supply dues anda waste gas tlue arranged intermediate said air supply lues, the innerstacks between waste gas and air sup ply tiues being` made ot materialwhich a conductor ot heat and said stacks being` corrugated, the lowerends of said air sup ply ilues being adapted to be connected with thecombustionchamber of a furnace and being provided at their upperendswith air supply connections, the lower end ot the waste gas tluebeing adapted for connection with the waste gas space of a furnace andmeans for creating a circulation ot air in said air supply iiues in adirection opposite to the circulation ot waste gases in said waste tine,substantially as described.

7. ln a recuperator, of the type speciiied, the combination of kaplurality of stacks arranged one within another forming separate linescomprising air supply i'iues and a waste gas flue arranged intermediatesail air supply iiues, the intermediate stack forming the Outer wall otthe waste gas "due coni-y prising an extension at. its lower end whichextends across the outer air supply (lue and communicates with a holeformed in 'the outer stack, and a removable plate which closes the openlower end ot said extension, substantially as described.

8. In a recuperator of the type speciiied, thecombination of a pluralityof stacks arranged one within another forming separate iiues comprising`air supply fines and a waste gas i'lue arranged intermediate said airsupply liues. the intermediate stack forming the outer wall of the wastegas flue comprising a downwardly inclined extension at its lower endwhich extends across the outer air supply flue and communicates with ahole formed in the outer stack and a removable plate which closes theopen lower i! il ico the combination kof a plurality of stacks ar--ranged one Within another forming separate flues', comprising air supplyfines and a Waste gas Hue arranged intermediate said air supply liues,`the intermediate stack forming the outer Wall of the Waste gas fluecomprising an extension at its lower end which extends across the outer.air supply lue and communicates with a hole formed in the outer stack,and a removable plate i which closes the open lower end of saidextension, the lower end of the inner stack `itormingthe inner airsupply lue extending through the Wall of the extension o saidintermediate stack and being in open oommunication With the lower end ofthe outer air supply flue, Which is adapted tok be connected with thecombustion spaceof a furnace, substantially as described.

In testimony, that I claim the foregoing as my invention, I aHiX mysignature this 42th day of October A. D. 1920.

ROBERT SCHLEMM.

